1. Field of the Invention
The present invention relates to a method of managing the message path of an Offene Systeme and deren Schnittstellen für die Elektronik in Kraftfahrzeugen (OSEK) network. More particularly, the present invention relates to a method of, if a network failure has occurred at a specific node of an OSEK network, eliminating only the corresponding node from the path of the network path and then reestablishing a path.
2. Description of the Related Art
Units that are responsible for functions in automobiles corresponding to those of the brain and neurons of a human are an electronic control unit (ECU) and a communication network. Recently, the core mechanical units of automobiles, such as an engine, a transmission, a steering device, a braking device, a suspension, etc., have evolved in a direction that enables them to be more finely controlled and that provides more comfort and convenience to a driver and passengers. In line with this evolution, the number of ECUs has increased in proportion to the level of automobiles and the importance of ECUs is increasing.
OSEK is applied to 70% of operating systems (OSs) for automobiles, which are core software implementations that provide ECU operation environments. In a conventional OSEK-based communication network environment, although a Network Management (NM) forms a bus topology, it actually operates in a ring topology.
All nodes having IDs unique within a network transmit alive messages at the same time, thereby becoming aware of all linked nodes and then configuring a network. Based on the IDs of the respective IDs, a network system is managed, for example, in such a way that a node having an ID of 1 transmits data to a node having an ID of 2, the node having an ID of 2 transmits data to a node having an ID of 3 and so on in a sequential manner. Upon the transmission of such a message, each node transmits the message over a fixed constant time TMax.
If a network failure has occurred and thus a specific node has not transferred a message to a subsequent node within TMaxtime, this specific node becomes a failed node. Thereafter, in order to restore a network to a new ring topology path, a network is reset, and all nodes transmit alive messages at the same time and receive alive messages from all the other nodes, thereby reconfiguring the network. An NM makes the failed node be temporarily excluded from a ring topology path, and makes the failed node participate in the ring topology path when it normally operates again.
When the number of nodes in a network is large, a large amount of data is transmitted to a bus, and thus many problems, such as collision, retransmission, transmission time delay, etc., may occur, with the result that more reliable data transmission is required.